Rosemary needs a lot of light and warmth. To ensure that this Mediterranean herb also survives our cold season, it must be protected from frost and kept in a suitable location.
Rosemary (Rosmarinus officinalis) originally comes from the Mediterranean and is accustomed to sun and warmth. Therefore, it cannot cope with cold winter temperatures and frost. To ensure that this popular herb flourishes again in the following year, it needs special care throughout winter. Read on to find out everything you need to know about keeping rosemary alive in winter.
Is rosemary winter hardy?
No, rosemary plants are not usually winter hardy. Although the popular herb has some cold tolerance and can withstand temperatures around freezing point, the winter temperatures in many parts of the UK are too cold for it without protection. As a result, rosemary needs to be overwintered in a way that protects it from frost. You can find winter-hardy rosemary bush varieties in our overview of the most popular rosemary varieties.
Rosemary winter care
Since rosemary is very sensitive to frost, it must be sufficiently protected during the winter. There are also some other care measures that should be observed in winter. For example, stop fertilising the plant before overwintering. Also, water your rosemary plant from time to time to avoid drought stress. That said, the evergreen herb has a low water requirement even during the growing season, so be careful with watering. Avoid waterlogging and excessively moist soil, as rosemary is very sensitive to this and quickly develops root rot.
Overwintering the rosemary bush: instructions
There is a difference between overwintering rosemary in a bed or in a flowerpot. Here is a brief step-by-step guide to overwintering rosemary in both pots and beds.
Overwintering rosemary in beds
How to overwinter rosemary in a garden bed:
- Cover the soil as well as the plant with brushwood. You may want to put up a small metal frame and cover it with brushwood to keep the rosemary plant free from snow.
- The brushwood cover should be thick enough to provide protection while still allowing for air circulation.
- Instead of brushwood, you can also cover the ground with leaves or use mats or fleece that air and light permeable.
- Ideal location in winter: a sunny place sheltered against a house wall.
Note: rosemary can be killed by the combination of permanently frozen ground and bright and sunny winter days. Water evaporates from the evergreen plant under these conditions, and it is unable to draw more water from the frozen soil. This can lead to withering and death in winter.
Tip: do not harvest rosemary in winter. In summer, you can stock up on rosemary in preparation for the cold months.
Overwintering rosemary in pots
Potted rosemary survives winter best in a bright, cool place at 4 to 12°C. Suitable places for overwintering rosemary indoors could be a light and airy stairwell, a greenhouse, or a bright garage or cellar. Once you have found a suitable spot, simply leave the rosemary plant there over winter. It does not like changes in light or temperature. You can also overwinter large rosemary pots outdoors, providing you insulate the pot with foil or fleece that protects the soil from freezing all the way through. Then, choose a sheltered but sunny spot for the plant, such as a balcony or against a wall.
Rosemary is a popular Mediterranean herb for seasoning food. Find out how to cut and harvest rosemary correctly in our dedicated article.